During the launch of STS-100, Chris Hadfield sat on the flight deck behind the Commander and the pilot. His job during the eight and a half minutes it took the Shuttle to reach orbit was to provide backup to the two pilots, especially if anything were to go wrong. During this critical, fast-paced portion of the flight, failures could have life-threatening consequences and decisions must be made instantaneously.
Hadfield spent hundreds of hours in simulators on the ground training for different "abort scenarios"—procedures for landing the Shuttle if the engines shut down too soon to achieve a proper orbit. Depending on when that happens, the Shuttle could return to the runway at the Kennedy Space Center, land in Morocco or go once around the Earth to land in California.
One of Hadfield’s tasks during such an emergency would be to rapidly assess the impact on the Shuttle’s ability to land if several systems failed at the same time. "If you lose this system, plus this system, plus this system, what does that mean in the next 30 seconds and for the rest of the flight? About three minutes from landing, it’s up to me summarize everything that failed, which systems are going to work and which aren’t."
Hadfield’s first task, just minutes after the Shuttle reached orbit, was to take pictures of the large External Tank, which was cut loose after exhausting its supply of fuel for the Shuttle’s main engines. The tank burns up in the atmosphere, so there’s no way to examine it for damage back on Earth. "I have to quickly stuff away my gloves and helmet, get a camera, get up and take pictures of the tank as it tumbles away from us," Hadfield said.
The second day of the mission was spent chasing the International Space Station in preparation for docking, and also spent checking out equipment aboard the Shuttle, including the suits that were used during the spacewalks. On the third day, Endeavour rendezvoused with the Station, docking to the US-built laboratory, Destiny.
During the rendezvous, Hadfield managed instruments and computers that provided data on how fast the Shuttle was closing on the Station and the distance between the two vehicles. He was also responsible for ensuring that the docking system that links the two vehicles was working properly so the Shuttle crew could later use its hatch to enter the Station.